Multi-purpose adjustable retaining device



FIG. 1 is a top plan view of a multi-purpose adjustable retaining device showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a left side view thereof; and,

FIG. 4 is a right side view thereof.

The broken lines depict portions of the multi-purpose adjustable retaining device that form no part of the claimed design. 

CLAIM The ornamental design for a multi-purpose adjustable retaining device, as shown and described. 